Mitsubishi Electric MR-JE-C Series, Инструкция по эксплуатации

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3. Modbus/TCP
3 - 4
3.6 Function Codes
3.6.1 List of function codes
The MR-JE-_C servo amplifier supports the following function codes.
Code Function name Description
03h Read Holding Registers Reading data in holding registers
The data in the registered holding registers can be read from the client.
08h Diagnostics Function diagnostics
When this function code is sent from the client to a server, the server returns the
received data to the client without any changes.
Communication checks can be performed.
10h Preset Multiple Registers Writing data in multiple holding registers
Consecutive multiple data sets can be written in the registered holding registers from
the client.
3.6.2 Read Holding Registers (Reading data in holding registers: 03h)
Data in consecutive registers is read for the specified number of data points starting from the specified
register address.
(1) Message frame
Query Message
Transaction
Identifier
Protocol
Identifier
Length Field
Unit
Identifier
Function
Starting Address No. of Points
H L H L
16 bits 0000h 0006h FFh 03h 8 bits 8 bits 8 bits 8 bits
Message field Size Description
Transaction Identifier 16 bits Set any value.
Protocol Identifier 16 bits Set "0000h".
Length Field 16 bits Set "0006h".
Unit Identifier 8 bits Set "FFh".
Function 8 bits Set "03h".
Starting Address (Note) 16 bits Set a start address of the holding registers to read.
No. of Points 16 bits Set the number of points of data to read starting from the start address of the
holding registers from which data is read.
Set the number of read points described in the list of holding registers.
To read the data in continuous registers, set a value obtained by adding the
number of read points of the target registers to this number.
Note. Registers can be classified into two types: registers that can be continuously accessed and particular registers that cannot be
continuously accessed.
To read particular registers, read only the target registers.
For the details on whether the target registers can be continuously accessed or not, refer to chapter 7.